In summer, domestic animals generally drink much water but show decreased appetite, which causes various problems, for example, in the case of pig etc., stagnation in body weight gain and reduction of mating performance, in the case of broiler etc., stagnation in body weight gain, in the case of layer etc., reduction of egg laying performance, decrease in egg shell strength and increase in the ratio of soft/broken shell eggs.
Further, problems such as stagnation in body weight gain may occur at the time of the shipment of broilers, the transfer of large layer chicks, the debeaking of layers, forced moulting of layers, the change of the feed for layers or broilers, the first feeding of the new-born layers or broilers, vaccination of layers or broilers, farrowing and weaning of piglings and the shipment of mother pigs.
To prevent these problems, attempts have been made to add nutritional components such as amino acids to feeds to thereby improve the nutritional conditions of domestic animals.
Even if nutritional components such as amino acids are added to feeds, however, the decreased appetite makes it impossible to achieve the desired effects.
In addition, feed remaining in the digestive organs of pork type pigs, broilers etc. at dressing contravenes the Food Hygiene Law. It is therefore necessary to omit feed and give only water to domestic animals from the day before shipment.
Accordingly, it is expected that when nutritional components including amino acids are added to drinking water, then the nutritional conditions of domestic animals can be maintained or improved even though they show decreased appetite or are fasting.
JP-A-2-255047 has proposed a method for improving the amino acid uptake of an animal by orally administering a liquid composition comprising amino acids together with other nutritional components, for example, carbohydrates, vitamins, minerals and enzymes (the term "JP-A" as used herein means an "unexamined published Japanese patent application").
However, the composition disclosed in the above publication suffers from several disadvantages, for example that a sufficient amount of amino acids can be hardly dissolved in the composition and that glucose, which is one of the carbohydrates employed as an additive, undergoes aminocarbonylation with the amino acids in an aqueous solution resulting in browning or solidification of the feed aqueous solution. U.S. Pat. No. 5,296,243 discloses a method using sugar alcohol in place of sugar, but a more effective nourishing method has been desired.